<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>增加年龄</title>
</head>
<body>
    
</body>
<script>
let age = prompt('你现在多少岁了？')
let s = Number(age) + 5
document.write('据我估计，五年后，你可能' + s + '岁了')
</script>
</html>